San Francisco and Woodlands, TX – Blackline Partners LLC, a leader in providing customer-focused midstream logistics and infrastructure solutions for the North American energy markets, and TPG Sixth Street Partners (“TSSP”), a global credit and credit-related investment firm, today announced the formation of Blackline Midstream, a growth oriented joint venture with the purpose of acquiring and developing oil and gas midstream infrastructure assets.

In conjunction with the joint venture formation, Blackline Midstream has acquired SEA-3, Inc. (“SEA-3”), owner of New England’s premier propane storage and distribution terminal located in Newington, New Hampshire from Trammo, Inc. Trammo’s Houston, TX team previously dedicated to the SEA-3 business have joined Blackline Midstream and will operate from the Blackline Midstream office in Houston, TX. In addition, all of SEA-3’s New Hampshire based terminal operating personnel will remain in place.

SEA-3’s assets consist of 530,000 barrels of propane storage, a 5-lane 24/7 truck loading rack, an ocean-access marine vessel receiving/loading dock, and a 6-spot rail receiving rack. In addition, SEA-3 has a fully approved upgrade project which will significantly increase the rail unloading capacity of the terminal giving it access to both domestic and international markets.

“Blackline’s deeply experienced operations management team combined with TSSP’s financial strength and expertise position us to integrate SEA-3 into a strong, well-equipped midstream growth platform,” said Mike Day, CEO of Blackline Partners. “We will immediately commence the rail expansion project at Newington in order to position SEA-3 as the most flexible and reliable propane supply terminal in the Northeast United States. On a personal note, as a native of New England, it is a privilege to be able to invest in the people and infrastructure of New England that serve the energy needs of the region.”

“With the rail expansion project, we will be able to remain competitive under any market supply scenario,” added David Herr, VP of Marketing at Blackline, who will be managing product commercial operations for Blackline Midstream. “All existing commercial agreements will be carried forward, and customers of the terminal will experience a seamless transition following the acquisition.”

About Blackline Midstream

Blackline Midstream is a growth oriented midstream company jointly owned by TPG Sixth Street Partners and Blackline Partners formed to develop and acquire midstream oil & gas and related assets. Blackline’s core values include an intensive focus on the safety, reliability, environmental stewardship and regulatory compliance of its operations and a positive contribution to the communities in which it operates. The management team at Blackline has extensive experience developing and operating large scale transportation and logistics assets for oil & gas customers across North America. Prior experience includes long term careers with Shell Oil and the BNSF Railway and the successful completion of over a dozen major ground up terminal developments during their decade long involvement with US Development Group. Blackline Midstream is headquartered in The Woodlands, TX.

About TPG Sixth Street Partners

TPG Sixth Street Partners (“TSSP”) is the global credit and credit-related investment platform partnered with TPG. Co-founded in 2009 by Chief Investment Officer Alan Waxman, TSSP has approximately $21 billion in assets under management. TSSP has a long-term oriented, highly flexible capital base that allows it to invest across industries, geographies, capital structures and asset classes. TSSP’s investments are typically complex to source, analyze and execute. For more information, please visit

About Blackline Partners

Blackline Partners, LLC and its affiliates provide customer focused midstream logistics and infrastructure solutions for the North American energy markets. Our solutions target upstream producers, midstream companies, downstream refiners, product marketers and traders and our team has extensive experience developing, owning and operating logistics terminals and assets. As we continue to expand our midstream footprint, we remain committed to delivering safe, efficient and sustainable value-added services for our clients and customers.


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Bill Swan
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